Investigation of adsorption and corrosion inhibition property of Hyperoside as a novel corrosion inhibitor for Q235 steel in HaCl medium

Abstract

Plant extracts have been widely reported as promising green metal corrosion inhibitors in recent years. Due to abundant sources, low cost and no pollution to the environment, plant extracts are good raw materials for preparing corrosion inhibitors. However, they have not been successfully applied in the corrosion industry owing to their unknown composition and large dosage. To further explore the effective corrosion inhibitors in plant extracts, Hyperoside (HYP) is firstly isolated from Uncaria laevigata in this work. Here, we assume that HYP shows good corrosion inhibition performance for Q235 steel in acidic medium. Then, the corrosion inhibition performance of HYP on Q235 steel in 1 M HCl solution at different temperature and corrosion time was explored by experiments and theoretical calculations. Electrochemical experiments showed that the corrosion inhibition efficiency of 300 mg/L HYP on Q235 steel in 1 M HCl was 92.34 % at 25 °C for 24 h. Excitedly, HYP (300 mg/L) still revealed a high corrosion inhibition efficiency of 80.49 % at 85 °C. Surface analysis showed that HYP formed a protective film on the steel surface. Additionally, quantum chemical calculation and molecular dynamics simulation evaluated the corrosion inhibition mechanism of HYP at the molecular level. The outstanding advantages of HYP over some plant extracts include low dosage, clear structure and sustained protection. Therefore, it can be used as a green corrosion inhibitor and shows great application prospect in oil well acidification with high temperature. Meanwhile, this work will provide some ideas for exploring the monomer or compound components that really exert inhibition effect in plant extracts.